Improved unicode fileio support.
[reactos.git] / reactos / lib / msvcrt / time / ctime.c
1
2 // fix djdir
3
4 /* Copyright (C) 1995 DJ Delorie, see COPYING.DJ for details */
5 /* This file has been modified by DJ Delorie. These modifications are
6 ** Copyright (C) 1995 DJ Delorie, 24 Kirsten Ave, Rochester NH,
7 ** 03867-2954, USA.
8 */
9
10 /*
11 * Copyright (c) 1987, 1989 Regents of the University of California.
12 * All rights reserved.
13 *
14 * This code is derived from software contributed to Berkeley by
15 * Arthur David Olson of the National Cancer Institute.
16 *
17 * Redistribution and use in source and binary forms are permitted provided
18 * that: (1) source distributions retain this entire copyright notice and
19 * comment, and (2) distributions including binaries display the following
20 * acknowledgement: ``This product includes software developed by the
21 * University of California, Berkeley and its contributors'' in the
22 * documentation or other materials provided with the distribution and in
23 * all advertising materials mentioning features or use of this software.
24 * Neither the name of the University nor the names of its contributors may
25 * be used to endorse or promote products derived from this software without
26 * specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
28 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
29 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
30 */
31
32 /*
33 ** Leap second handling from Bradley White (bww@k.gp.cs.cmu.edu).
34 ** POSIX-style TZ environment variable handling from Guy Harris
35 ** (guy@auspex.com).
36 */
37
38 #include <msvcrt/fcntl.h>
39 #include <msvcrt/time.h>
40 #include <msvcrt/string.h>
41 #include <msvcrt/ctype.h>
42 #include <msvcrt/stdio.h>
43 #include <msvcrt/stdlib.h>
44
45 #include <windows.h>
46 #include "tzfile.h"
47
48 #include <msvcrt/io.h>
49
50 #include "posixrul.h"
51
52
53 #ifdef __cplusplus
54 #define CPP_CONST const
55 #else
56 #define CPP_CONST
57 #endif
58
59 #define P(s) s
60 #define alloc_size_t size_t
61 #define qsort_size_t size_t
62 #define fread_size_t size_t
63 #define fwrite_size_t size_t
64
65 #define ACCESS_MODE O_RDONLY|O_BINARY
66 #define OPEN_MODE O_RDONLY|O_BINARY
67
68 /*
69 ** Someone might make incorrect use of a time zone abbreviation:
70 ** 1. They might reference tzname[0] before calling tzset (explicitly
71 ** or implicitly).
72 ** 2. They might reference tzname[1] before calling tzset (explicitly
73 ** or implicitly).
74 ** 3. They might reference tzname[1] after setting to a time zone
75 ** in which Daylight Saving Time is never observed.
76 ** 4. They might reference tzname[0] after setting to a time zone
77 ** in which Standard Time is never observed.
78 ** 5. They might reference tm.TM_ZONE after calling offtime.
79 ** What's best to do in the above cases is open to debate;
80 ** for now, we just set things up so that in any of the five cases
81 ** WILDABBR is used. Another possibility: initialize tzname[0] to the
82 ** string "tzname[0] used before set", and similarly for the other cases.
83 ** And another: initialize tzname[0] to "ERA", with an explanation in the
84 ** manual page of what this "time zone abbreviation" means (doing this so
85 ** that tzname[0] has the "normal" length of three characters).
86 */
87
88 void _set_daylight_export(int);
89 void _set_timezone_export(int);
90
91
92 static char WILDABBR[] = " ";
93
94 #ifndef TRUE
95 #define TRUE 1
96 #define FALSE 0
97 #endif /* !defined TRUE */
98
99 static const char GMT[] = "GMT";
100
101 struct ttinfo { /* time type information */
102 long tt_gmtoff; /* GMT offset in seconds */
103 int tt_isdst; /* used to set tm_isdst */
104 int tt_abbrind; /* abbreviation list index */
105 int tt_ttisstd; /* TRUE if transition is std time */
106 };
107
108 struct lsinfo { /* leap second information */
109 time_t ls_trans; /* transition time */
110 long ls_corr; /* correction to apply */
111 };
112
113 struct state {
114 int leapcnt;
115 int timecnt;
116 int typecnt;
117 int charcnt;
118 time_t ats[TZ_MAX_TIMES];
119 unsigned char types[TZ_MAX_TIMES];
120 struct ttinfo ttis[TZ_MAX_TYPES];
121 char chars[(TZ_MAX_CHARS + 1 > sizeof GMT) ? TZ_MAX_CHARS + 1 : sizeof GMT];
122 struct lsinfo lsis[TZ_MAX_LEAPS];
123 };
124
125 struct rule {
126 int r_type; /* type of rule--see below */
127 int r_day; /* day number of rule */
128 int r_week; /* week number of rule */
129 int r_mon; /* month number of rule */
130 long r_time; /* transition time of rule */
131 };
132
133 #define JULIAN_DAY 0 /* Jn - Julian day */
134 #define DAY_OF_YEAR 1 /* n - day of year */
135 #define MONTH_NTH_DAY_OF_WEEK 2 /* Mm.n.d - month, week, day of week */
136
137 /*
138 ** Prototypes for static functions.
139 */
140 #if 0
141 static long detzcode P((const char * codep));
142 static const char * getzname P((const char * strp));
143 static const char * getnum P((const char * strp, int * nump, int min, int max));
144 static const char * getsecs P((const char * strp, long * secsp));
145 static const char * getoffset P((const char * strp, long * offsetp));
146 static const char * getrule P((const char * strp, struct rule * rulep));
147 static void gmtload P((struct state * sp));
148 static void gmtsub P((const time_t * timep, long offset, struct tm * tmp));
149 static void localsub P((const time_t * timep, long offset, struct tm * tmp));
150 static void normalize P((int * tensptr, int * unitsptr, int base));
151 static void settzname P((void));
152 static time_t time1 P((struct tm * tmp, void (* funcp)(const time_t * CPP_CONST, const long, struct tm * CPP_CONST), long offset));
153 static time_t time2 P((struct tm *tmp, void (* funcp)(const time_t * CPP_CONST, const long, struct tm * CPP_CONST), long offset, int * okayp));
154 static void timesub P((const time_t * timep, long offset, const struct state * sp, struct tm * tmp));
155 static int tmcomp P((const struct tm * atmp, const struct tm * btmp));
156 static time_t transtime P((time_t janfirst, int year, const struct rule * rulep, long offset));
157 static int tzload P((const char * name, struct state * sp));
158 static int tzparse P((const char * name, struct state * sp, int lastditch));
159 static void tzsetwall(void);
160
161 #else
162
163 static const char * getnum(const char * strp, int * CPP_CONST nump, const int min, const int max);
164 static void timesub(const time_t * CPP_CONST timep, const long offset, const struct state * CPP_CONST sp, struct tm * CPP_CONST tmp);
165 static time_t transtime(const time_t janfirst, const int year, const struct rule * CPP_CONST rulep, const long offset);
166 static void tzsetwall(void);
167
168 #endif
169
170 #ifdef ALL_STATE
171 static struct state *lclptr;
172 static struct state *gmtptr;
173 #endif /* defined ALL_STATE */
174
175 #ifndef ALL_STATE
176 static struct state lclmem;
177 static struct state gmtmem;
178 #define lclptr (&lclmem)
179 #define gmtptr (&gmtmem)
180 #endif /* State Farm */
181
182 static int lcl_is_set;
183 static int gmt_is_set;
184
185 char * _tzname[2] = {
186 WILDABBR,
187 WILDABBR
188 };
189
190 static long
191 detzcode(const char * CPP_CONST codep)
192 {
193 long result;
194 int i;
195
196 result = 0;
197 for (i = 0; i < 4; ++i)
198 result = (result << 8) | (codep[i] & 0xff);
199 return result;
200 }
201
202 static void
203 settzname(void)
204 {
205 const struct state * CPP_CONST sp = lclptr;
206 int i;
207
208 _tzname[0] = WILDABBR;
209 _tzname[1] = WILDABBR;
210 #ifdef ALL_STATE
211 if (sp == NULL)
212 {
213 _tzname[0] = _tzname[1] = GMT;
214 return;
215 }
216 #endif /* defined ALL_STATE */
217 for (i = 0; i < sp->typecnt; ++i)
218 {
219 register const struct ttinfo * CPP_CONST ttisp = &sp->ttis[i];
220
221 _tzname[ttisp->tt_isdst] =
222 (char *)&sp->chars[ttisp->tt_abbrind];
223 #if 0
224 if (ttisp->tt_isdst) {
225 //_daylight = 1;
226 _set_daylight_export(1);
227 }
228 if (i == 0 || !ttisp->tt_isdst) {
229 //_timezone_dll = -(ttisp->tt_gmtoff);
230 _set_timezone_export(-(ttisp->tt_gmtoff));
231 }
232 if (i == 0 || ttisp->tt_isdst) {
233 _altzone = -(ttisp->tt_gmtoff);
234 }
235 #endif
236 }
237 /*
238 ** And to get the latest zone names into tzname. . .
239 */
240 for (i = 0; i < sp->timecnt; ++i)
241 {
242 const struct ttinfo * CPP_CONST ttisp = &sp->ttis[sp->types[i]];
243
244 _tzname[ttisp->tt_isdst] = (char *)&sp->chars[ttisp->tt_abbrind];
245 }
246 }
247
248 static char* tzdir(void)
249 {
250 static char dir[80]={0}, *cp;
251 if (dir[0] == 0)
252 {
253 if ((cp = getenv("TZDIR")))
254 {
255 strcpy(dir, cp);
256 }
257 else if ((cp = getenv("DJDIR")))
258 {
259 strcpy(dir, cp);
260 strcat(dir, "/zoneinfo");
261 }
262 else
263 strcpy(dir, "./");
264 }
265 return dir;
266 }
267
268 static int tzload(const char* name, struct state* CPP_CONST sp)
269 {
270 const char * p;
271 int i;
272 int fid;
273 char fullname[FILENAME_MAX + 1];
274 const struct tzhead * tzhp;
275 char buf[sizeof *sp + sizeof *tzhp];
276 int ttisstdcnt;
277
278 if (name == NULL && (name = TZDEFAULT) == NULL)
279 return -1;
280
281 if (name[0] == ':')
282 ++name;
283 if (name[0] != '/')
284 {
285 if ((p = tzdir()) == NULL)
286 return -1;
287 if ((strlen(p) + strlen(name) + 1) >= sizeof fullname)
288 return -1;
289 strcpy(fullname, p);
290 strcat(fullname, "/");
291 strcat(fullname, name);
292 name = fullname;
293 }
294
295 if ((fid = open(name, OPEN_MODE)) == -1)
296 {
297 const char *base = strrchr(name, '/');
298 if (base)
299 base++;
300 else
301 base = name;
302 if (strcmp(base, "posixrules"))
303 return -1;
304
305 /* We've got a built-in copy of posixrules just in case */
306 memcpy(buf, _posixrules_data, sizeof(_posixrules_data));
307 i = sizeof(_posixrules_data);
308 }
309 else
310 {
311 i = read(fid, buf, sizeof buf);
312 if (close(fid) != 0 || i < sizeof *tzhp)
313 return -1;
314 }
315
316 tzhp = (struct tzhead *) buf;
317 ttisstdcnt = (int) detzcode(tzhp->tzh_ttisstdcnt);
318 sp->leapcnt = (int) detzcode(tzhp->tzh_leapcnt);
319 sp->timecnt = (int) detzcode(tzhp->tzh_timecnt);
320 sp->typecnt = (int) detzcode(tzhp->tzh_typecnt);
321 sp->charcnt = (int) detzcode(tzhp->tzh_charcnt);
322 if (sp->leapcnt < 0 || sp->leapcnt > TZ_MAX_LEAPS ||
323 sp->typecnt <= 0 || sp->typecnt > TZ_MAX_TYPES ||
324 sp->timecnt < 0 || sp->timecnt > TZ_MAX_TIMES ||
325 sp->charcnt < 0 || sp->charcnt > TZ_MAX_CHARS ||
326 (ttisstdcnt != sp->typecnt && ttisstdcnt != 0))
327 return -1;
328 if (i < sizeof *tzhp +
329 sp->timecnt * (4 + sizeof (char)) +
330 sp->typecnt * (4 + 2 * sizeof (char)) +
331 sp->charcnt * sizeof (char) +
332 sp->leapcnt * 2 * 4 +
333 ttisstdcnt * sizeof (char))
334 return -1;
335 p = buf + sizeof *tzhp;
336 for (i = 0; i < sp->timecnt; ++i)
337 {
338 sp->ats[i] = detzcode(p);
339 p += 4;
340 }
341 for (i = 0; i < sp->timecnt; ++i)
342 {
343 sp->types[i] = (unsigned char) *p++;
344 if (sp->types[i] >= sp->typecnt)
345 return -1;
346 }
347 for (i = 0; i < sp->typecnt; ++i)
348 {
349 struct ttinfo * ttisp;
350
351 ttisp = &sp->ttis[i];
352 ttisp->tt_gmtoff = detzcode(p);
353 p += 4;
354 ttisp->tt_isdst = (unsigned char) *p++;
355 if (ttisp->tt_isdst != 0 && ttisp->tt_isdst != 1)
356 return -1;
357 ttisp->tt_abbrind = (unsigned char) *p++;
358 if (ttisp->tt_abbrind < 0 ||
359 ttisp->tt_abbrind > sp->charcnt)
360 return -1;
361 }
362 for (i = 0; i < sp->charcnt; ++i)
363 sp->chars[i] = *p++;
364 sp->chars[i] = '\0'; /* ensure '\0' at end */
365 for (i = 0; i < sp->leapcnt; ++i)
366 {
367 struct lsinfo * lsisp;
368
369 lsisp = &sp->lsis[i];
370 lsisp->ls_trans = detzcode(p);
371 p += 4;
372 lsisp->ls_corr = detzcode(p);
373 p += 4;
374 }
375 for (i = 0; i < sp->typecnt; ++i)
376 {
377 struct ttinfo * ttisp;
378
379 ttisp = &sp->ttis[i];
380 if (ttisstdcnt == 0)
381 ttisp->tt_ttisstd = FALSE;
382 else
383 {
384 ttisp->tt_ttisstd = *p++;
385 if (ttisp->tt_ttisstd != TRUE &&
386 ttisp->tt_ttisstd != FALSE)
387 return -1;
388 }
389 }
390 return 0;
391 }
392
393 static const int mon_lengths[2][MONSPERYEAR] = {
394 { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 },
395 { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }
396 };
397
398 static const int year_lengths[2] = {
399 DAYSPERNYEAR, DAYSPERLYEAR
400 };
401
402 /*
403 ** Given a pointer into a time zone string, scan until a character that is not
404 ** a valid character in a zone name is found. Return a pointer to that
405 ** character.
406 */
407
408 static const char*
409 getzname(const char* strp)
410 {
411 char c;
412
413 while ((c = *strp) != '\0' && !isdigit(c) && c != ',' && c != '-' &&
414 c != '+')
415 ++strp;
416 return strp;
417 }
418
419 /*
420 ** Given a pointer into a time zone string, extract a number from that string.
421 ** Check that the number is within a specified range; if it is not, return
422 ** NULL.
423 ** Otherwise, return a pointer to the first character not part of the number.
424 */
425
426 static const char*
427 getnum(const char* strp, int* CPP_CONST nump, const int min, const int max)
428 {
429 char c;
430 int num;
431
432 if (strp == NULL || !isdigit(*strp))
433 return NULL;
434 num = 0;
435 while ((c = *strp) != '\0' && isdigit(c))
436 {
437 num = num * 10 + (c - '0');
438 if (num > max)
439 return NULL;
440 ++strp;
441 }
442 if (num < min)
443 return NULL;
444 *nump = num;
445 return strp;
446 }
447
448 /*
449 ** Given a pointer into a time zone string, extract a number of seconds,
450 ** in hh[:mm[:ss]] form, from the string.
451 ** If any error occurs, return NULL.
452 ** Otherwise, return a pointer to the first character not part of the number
453 ** of seconds.
454 */
455
456 static const char *
457 getsecs(const char *strp, long * CPP_CONST secsp)
458 {
459 int num;
460
461 strp = getnum(strp, &num, 0, HOURSPERDAY);
462 if (strp == NULL)
463 return NULL;
464 *secsp = num * SECSPERHOUR;
465 if (*strp == ':')
466 {
467 ++strp;
468 strp = getnum(strp, &num, 0, MINSPERHOUR - 1);
469 if (strp == NULL)
470 return NULL;
471 *secsp += num * SECSPERMIN;
472 if (*strp == ':')
473 {
474 ++strp;
475 strp = getnum(strp, &num, 0, SECSPERMIN - 1);
476 if (strp == NULL)
477 return NULL;
478 *secsp += num;
479 }
480 }
481 return strp;
482 }
483
484 /*
485 ** Given a pointer into a time zone string, extract an offset, in
486 ** [+-]hh[:mm[:ss]] form, from the string.
487 ** If any error occurs, return NULL.
488 ** Otherwise, return a pointer to the first character not part of the time.
489 */
490
491 static const char *
492 getoffset(const char *strp, long * CPP_CONST offsetp)
493 {
494 int neg;
495
496 if (*strp == '-')
497 {
498 neg = 1;
499 ++strp;
500 }
501 else if (isdigit(*strp) || *strp++ == '+')
502 neg = 0;
503 else
504 return NULL; /* illegal offset */
505 strp = getsecs(strp, offsetp);
506 if (strp == NULL)
507 return NULL; /* illegal time */
508 if (neg)
509 *offsetp = -*offsetp;
510 return strp;
511 }
512
513 /*
514 ** Given a pointer into a time zone string, extract a rule in the form
515 ** date[/time]. See POSIX section 8 for the format of "date" and "time".
516 ** If a valid rule is not found, return NULL.
517 ** Otherwise, return a pointer to the first character not part of the rule.
518 */
519
520 static const char *
521 getrule(const char *strp, struct rule * CPP_CONST rulep)
522 {
523 if (*strp == 'J')
524 {
525 /*
526 ** Julian day.
527 */
528 rulep->r_type = JULIAN_DAY;
529 ++strp;
530 strp = getnum(strp, &rulep->r_day, 1, DAYSPERNYEAR);
531 }
532 else if (*strp == 'M')
533 {
534 /*
535 ** Month, week, day.
536 */
537 rulep->r_type = MONTH_NTH_DAY_OF_WEEK;
538 ++strp;
539 strp = getnum(strp, &rulep->r_mon, 1, MONSPERYEAR);
540 if (strp == NULL)
541 return NULL;
542 if (*strp++ != '.')
543 return NULL;
544 strp = getnum(strp, &rulep->r_week, 1, 5);
545 if (strp == NULL)
546 return NULL;
547 if (*strp++ != '.')
548 return NULL;
549 strp = getnum(strp, &rulep->r_day, 0, DAYSPERWEEK - 1);
550 }
551 else if (isdigit(*strp))
552 {
553 /*
554 ** Day of year.
555 */
556 rulep->r_type = DAY_OF_YEAR;
557 strp = getnum(strp, &rulep->r_day, 0, DAYSPERLYEAR - 1);
558 }
559 else
560 return NULL; /* invalid format */
561 if (strp == NULL)
562 return NULL;
563 if (*strp == '/')
564 {
565 /*
566 ** Time specified.
567 */
568 ++strp;
569 strp = getsecs(strp, &rulep->r_time);
570 }
571 else
572 rulep->r_time = 2 * SECSPERHOUR; /* default = 2:00:00 */
573 return strp;
574 }
575
576 /*
577 ** Given the Epoch-relative time of January 1, 00:00:00 GMT, in a year, the
578 ** year, a rule, and the offset from GMT at the time that rule takes effect,
579 ** calculate the Epoch-relative time that rule takes effect.
580 */
581
582 static time_t
583 transtime(const time_t janfirst, const int year, const struct rule * CPP_CONST rulep, const long offset)
584 {
585 int leapyear;
586 time_t value=0;
587 int i;
588 int d, m1, yy0, yy1, yy2, dow;
589
590 leapyear = isleap(year);
591 switch (rulep->r_type)
592 {
593
594 case JULIAN_DAY:
595 /*
596 ** Jn - Julian day, 1 == January 1, 60 == March 1 even in leap
597 ** years.
598 ** In non-leap years, or if the day number is 59 or less, just
599 ** add SECSPERDAY times the day number-1 to the time of
600 ** January 1, midnight, to get the day.
601 */
602 value = janfirst + (rulep->r_day - 1) * SECSPERDAY;
603 if (leapyear && rulep->r_day >= 60)
604 value += SECSPERDAY;
605 break;
606
607 case DAY_OF_YEAR:
608 /*
609 ** n - day of year.
610 ** Just add SECSPERDAY times the day number to the time of
611 ** January 1, midnight, to get the day.
612 */
613 value = janfirst + rulep->r_day * SECSPERDAY;
614 break;
615
616 case MONTH_NTH_DAY_OF_WEEK:
617 /*
618 ** Mm.n.d - nth "dth day" of month m.
619 */
620 value = janfirst;
621 for (i = 0; i < rulep->r_mon - 1; ++i)
622 value += mon_lengths[leapyear][i] * SECSPERDAY;
623
624 /*
625 ** Use Zeller's Congruence to get day-of-week of first day of
626 ** month.
627 */
628 m1 = (rulep->r_mon + 9) % 12 + 1;
629 yy0 = (rulep->r_mon <= 2) ? (year - 1) : year;
630 yy1 = yy0 / 100;
631 yy2 = yy0 % 100;
632 dow = ((26 * m1 - 2) / 10 +
633 1 + yy2 + yy2 / 4 + yy1 / 4 - 2 * yy1) % 7;
634 if (dow < 0)
635 dow += DAYSPERWEEK;
636
637 /*
638 ** "dow" is the day-of-week of the first day of the month. Get
639 ** the day-of-month (zero-origin) of the first "dow" day of the
640 ** month.
641 */
642 d = rulep->r_day - dow;
643 if (d < 0)
644 d += DAYSPERWEEK;
645 for (i = 1; i < rulep->r_week; ++i)
646 {
647 if (d + DAYSPERWEEK >=
648 mon_lengths[leapyear][rulep->r_mon - 1])
649 break;
650 d += DAYSPERWEEK;
651 }
652
653 /*
654 ** "d" is the day-of-month (zero-origin) of the day we want.
655 */
656 value += d * SECSPERDAY;
657 break;
658 }
659
660 /*
661 ** "value" is the Epoch-relative time of 00:00:00 GMT on the day in
662 ** question. To get the Epoch-relative time of the specified local
663 ** time on that day, add the transition time and the current offset
664 ** from GMT.
665 */
666 return value + rulep->r_time + offset;
667 }
668
669 /*
670 ** Given a POSIX section 8-style TZ string, fill in the rule tables as
671 ** appropriate.
672 */
673
674 static int
675 tzparse(const char *name, struct state * CPP_CONST sp, const int lastditch)
676 {
677 const char * stdname;
678 const char * dstname=0;
679 int stdlen;
680 int dstlen;
681 long stdoffset;
682 long dstoffset;
683 time_t * atp;
684 unsigned char * typep;
685 char * cp;
686 int load_result;
687
688 stdname = name;
689 if (lastditch)
690 {
691 stdlen = strlen(name); /* length of standard zone name */
692 name += stdlen;
693 if (stdlen >= sizeof sp->chars)
694 stdlen = (sizeof sp->chars) - 1;
695 }
696 else
697 {
698 name = getzname(name);
699 stdlen = name - stdname;
700 if (stdlen < 3)
701 return -1;
702 }
703 if (*name == '\0')
704 return -1;
705 else
706 {
707 name = getoffset(name, &stdoffset);
708 if (name == NULL)
709 return -1;
710 }
711 load_result = tzload(TZDEFRULES, sp);
712 if (load_result != 0)
713 sp->leapcnt = 0; /* so, we're off a little */
714 if (*name != '\0')
715 {
716 dstname = name;
717 name = getzname(name);
718 dstlen = name - dstname; /* length of DST zone name */
719 if (dstlen < 3)
720 return -1;
721 if (*name != '\0' && *name != ',' && *name != ';')
722 {
723 name = getoffset(name, &dstoffset);
724 if (name == NULL)
725 return -1;
726 }
727 else
728 dstoffset = stdoffset - SECSPERHOUR;
729 if (*name == ',' || *name == ';')
730 {
731 struct rule start;
732 struct rule end;
733 int year;
734 time_t janfirst;
735 time_t starttime;
736 time_t endtime;
737
738 ++name;
739 if ((name = getrule(name, &start)) == NULL)
740 return -1;
741 if (*name++ != ',')
742 return -1;
743 if ((name = getrule(name, &end)) == NULL)
744 return -1;
745 if (*name != '\0')
746 return -1;
747 sp->typecnt = 2; /* standard time and DST */
748 /*
749 ** Two transitions per year, from EPOCH_YEAR to 2037.
750 */
751 sp->timecnt = 2 * (2037 - EPOCH_YEAR + 1);
752 if (sp->timecnt > TZ_MAX_TIMES)
753 return -1;
754 sp->ttis[0].tt_gmtoff = -dstoffset;
755 sp->ttis[0].tt_isdst = 1;
756 sp->ttis[0].tt_abbrind = stdlen + 1;
757 sp->ttis[1].tt_gmtoff = -stdoffset;
758 sp->ttis[1].tt_isdst = 0;
759 sp->ttis[1].tt_abbrind = 0;
760 atp = sp->ats;
761 typep = sp->types;
762 janfirst = 0;
763 for (year = EPOCH_YEAR; year <= 2037; ++year)
764 {
765 starttime = transtime(janfirst, year, &start,
766 stdoffset);
767 endtime = transtime(janfirst, year, &end,
768 dstoffset);
769 if (starttime > endtime)
770 {
771 *atp++ = endtime;
772 *typep++ = 1; /* DST ends */
773 *atp++ = starttime;
774 *typep++ = 0; /* DST begins */
775 }
776 else
777 {
778 *atp++ = starttime;
779 *typep++ = 0; /* DST begins */
780 *atp++ = endtime;
781 *typep++ = 1; /* DST ends */
782 }
783 janfirst +=
784 year_lengths[isleap(year)] * SECSPERDAY;
785 }
786 }
787 else
788 {
789 int sawstd;
790 int sawdst;
791 long stdfix;
792 long dstfix;
793 long oldfix;
794 int isdst;
795 int i;
796
797 if (*name != '\0')
798 return -1;
799 if (load_result != 0)
800 return -1;
801 /*
802 ** Compute the difference between the real and
803 ** prototype standard and summer time offsets
804 ** from GMT, and put the real standard and summer
805 ** time offsets into the rules in place of the
806 ** prototype offsets.
807 */
808 sawstd = FALSE;
809 sawdst = FALSE;
810 stdfix = 0;
811 dstfix = 0;
812 for (i = 0; i < sp->typecnt; ++i)
813 {
814 if (sp->ttis[i].tt_isdst)
815 {
816 oldfix = dstfix;
817 dstfix =
818 sp->ttis[i].tt_gmtoff + dstoffset;
819 if (sawdst && (oldfix != dstfix))
820 return -1;
821 sp->ttis[i].tt_gmtoff = -dstoffset;
822 sp->ttis[i].tt_abbrind = stdlen + 1;
823 sawdst = TRUE;
824 }
825 else
826 {
827 oldfix = stdfix;
828 stdfix =
829 sp->ttis[i].tt_gmtoff + stdoffset;
830 if (sawstd && (oldfix != stdfix))
831 return -1;
832 sp->ttis[i].tt_gmtoff = -stdoffset;
833 sp->ttis[i].tt_abbrind = 0;
834 sawstd = TRUE;
835 }
836 }
837 /*
838 ** Make sure we have both standard and summer time.
839 */
840 if (!sawdst || !sawstd)
841 return -1;
842 /*
843 ** Now correct the transition times by shifting
844 ** them by the difference between the real and
845 ** prototype offsets. Note that this difference
846 ** can be different in standard and summer time;
847 ** the prototype probably has a 1-hour difference
848 ** between standard and summer time, but a different
849 ** difference can be specified in TZ.
850 */
851 isdst = FALSE; /* we start in standard time */
852 for (i = 0; i < sp->timecnt; ++i)
853 {
854 const struct ttinfo * ttisp;
855
856 /*
857 ** If summer time is in effect, and the
858 ** transition time was not specified as
859 ** standard time, add the summer time
860 ** offset to the transition time;
861 ** otherwise, add the standard time offset
862 ** to the transition time.
863 */
864 ttisp = &sp->ttis[sp->types[i]];
865 sp->ats[i] +=
866 (isdst && !ttisp->tt_ttisstd) ?
867 dstfix : stdfix;
868 isdst = ttisp->tt_isdst;
869 }
870 }
871 }
872 else
873 {
874 dstlen = 0;
875 sp->typecnt = 1; /* only standard time */
876 sp->timecnt = 0;
877 sp->ttis[0].tt_gmtoff = -stdoffset;
878 sp->ttis[0].tt_isdst = 0;
879 sp->ttis[0].tt_abbrind = 0;
880 }
881 sp->charcnt = stdlen + 1;
882 if (dstlen != 0)
883 sp->charcnt += dstlen + 1;
884 if (sp->charcnt > sizeof sp->chars)
885 return -1;
886 cp = sp->chars;
887 (void) strncpy(cp, stdname, stdlen);
888 cp += stdlen;
889 *cp++ = '\0';
890 if (dstlen != 0)
891 {
892 (void) strncpy(cp, dstname, dstlen);
893 *(cp + dstlen) = '\0';
894 }
895 return 0;
896 }
897
898 static void
899 gmtload(struct state * CPP_CONST sp)
900 {
901 if (tzload(GMT, sp) != 0)
902 (void) tzparse(GMT, sp, TRUE);
903 }
904
905 void
906 _tzset(void)
907 {
908 const char * name;
909
910 name = getenv("TZ");
911 if (name == NULL)
912 {
913 tzsetwall();
914 return;
915 }
916 lcl_is_set = TRUE;
917 #ifdef ALL_STATE
918 if (lclptr == NULL)
919 {
920 lclptr = (struct state *) malloc(sizeof *lclptr);
921 if (lclptr == NULL)
922 {
923 settzname(); /* all we can do */
924 return;
925 }
926 }
927 #endif /* defined ALL_STATE */
928 if (*name == '\0')
929 {
930 /*
931 ** User wants it fast rather than right.
932 */
933 lclptr->leapcnt = 0; /* so, we're off a little */
934 lclptr->timecnt = 0;
935 lclptr->ttis[0].tt_gmtoff = 0;
936 lclptr->ttis[0].tt_abbrind = 0;
937 (void) strcpy(lclptr->chars, GMT);
938 }
939 else if (tzload(name, lclptr) != 0)
940 if (name[0] == ':' || tzparse(name, lclptr, FALSE) != 0)
941 gmtload(lclptr);
942 settzname();
943 }
944
945 void
946 tzsetwall(void)
947 {
948 lcl_is_set = TRUE;
949 #ifdef ALL_STATE
950 if (lclptr == NULL)
951 {
952 lclptr = (struct state *) malloc(sizeof *lclptr);
953 if (lclptr == NULL)
954 {
955 settzname(); /* all we can do */
956 return;
957 }
958 }
959 #endif /* defined ALL_STATE */
960 if (tzload((char *) NULL, lclptr) != 0)
961 gmtload(lclptr);
962 settzname();
963 }
964
965 /*
966 ** The easy way to behave "as if no library function calls" localtime
967 ** is to not call it--so we drop its guts into "localsub", which can be
968 ** freely called. (And no, the PANS doesn't require the above behavior--
969 ** but it *is* desirable.)
970 **
971 ** The unused offset argument is for the benefit of mktime variants.
972 */
973
974 /*ARGSUSED*/
975 static void
976 localsub(const time_t * CPP_CONST timep, const long offset, struct tm * CPP_CONST tmp)
977 {
978 const struct state * sp;
979 const struct ttinfo * ttisp;
980 int i;
981 const time_t t = *timep;
982
983 if (!lcl_is_set)
984 _tzset();
985 sp = lclptr;
986 #ifdef ALL_STATE
987 if (sp == NULL)
988 {
989 gmtsub(timep, offset, tmp);
990 return;
991 }
992 #endif /* defined ALL_STATE */
993 if (sp->timecnt == 0 || t < sp->ats[0])
994 {
995 i = 0;
996 while (sp->ttis[i].tt_isdst)
997 if (++i >= sp->typecnt)
998 {
999 i = 0;
1000 break;
1001 }
1002 }
1003 else
1004 {
1005 for (i = 1; i < sp->timecnt; ++i)
1006 if (t < sp->ats[i])
1007 break;
1008 i = sp->types[i - 1];
1009 }
1010 ttisp = &sp->ttis[i];
1011 /*
1012 ** To get (wrong) behavior that's compatible with System V Release 2.0
1013 ** you'd replace the statement below with
1014 ** t += ttisp->tt_gmtoff;
1015 ** timesub(&t, 0L, sp, tmp);
1016 */
1017 timesub(&t, ttisp->tt_gmtoff, sp, tmp);
1018 tmp->tm_isdst = ttisp->tt_isdst;
1019 _tzname[tmp->tm_isdst] = (char *)&sp->chars[ttisp->tt_abbrind];
1020 tmp->tm_zone = (char *)&sp->chars[ttisp->tt_abbrind];
1021 }
1022
1023 struct tm *
1024 localtime(const time_t * CPP_CONST timep)
1025 {
1026 static struct tm tm;
1027
1028 localsub(timep, 0L, &tm);
1029 return &tm;
1030 }
1031
1032 /*
1033 ** gmtsub is to gmtime as localsub is to localtime.
1034 */
1035
1036 static void
1037 gmtsub(const time_t * CPP_CONST timep, const long offset, struct tm * CPP_CONST tmp)
1038 {
1039 if (!gmt_is_set)
1040 {
1041 gmt_is_set = TRUE;
1042 #ifdef ALL_STATE
1043 gmtptr = (struct state *) malloc(sizeof *gmtptr);
1044 if (gmtptr != NULL)
1045 #endif /* defined ALL_STATE */
1046 gmtload(gmtptr);
1047 }
1048 timesub(timep, offset, gmtptr, tmp);
1049 /*
1050 ** Could get fancy here and deliver something such as
1051 ** "GMT+xxxx" or "GMT-xxxx" if offset is non-zero,
1052 ** but this is no time for a treasure hunt.
1053 */
1054 if (offset != 0)
1055 tmp->tm_zone = WILDABBR;
1056 else
1057 {
1058 #ifdef ALL_STATE
1059 if (gmtptr == NULL)
1060 tmp->TM_ZONE = GMT;
1061 else
1062 tmp->TM_ZONE = gmtptr->chars;
1063 #endif /* defined ALL_STATE */
1064 #ifndef ALL_STATE
1065 tmp->tm_zone = gmtptr->chars;
1066 #endif /* State Farm */
1067 }
1068 }
1069
1070 struct tm *
1071 gmtime(const time_t * CPP_CONST timep)
1072 {
1073 static struct tm tm;
1074
1075 gmtsub(timep, 0L, &tm);
1076 return &tm;
1077 }
1078
1079 static void
1080 timesub(const time_t * CPP_CONST timep, const long offset, const struct state * CPP_CONST sp, struct tm * CPP_CONST tmp)
1081 {
1082 const struct lsinfo * lp;
1083 long days;
1084 long rem;
1085 int y;
1086 int yleap;
1087 const int * ip;
1088 long corr;
1089 int hit;
1090 int i;
1091
1092 corr = 0;
1093 hit = FALSE;
1094 #ifdef ALL_STATE
1095 i = (sp == NULL) ? 0 : sp->leapcnt;
1096 #endif /* defined ALL_STATE */
1097 #ifndef ALL_STATE
1098 i = sp->leapcnt;
1099 #endif /* State Farm */
1100 while (--i >= 0)
1101 {
1102 lp = &sp->lsis[i];
1103 if (*timep >= lp->ls_trans)
1104 {
1105 if (*timep == lp->ls_trans)
1106 hit = ((i == 0 && lp->ls_corr > 0) ||
1107 lp->ls_corr > sp->lsis[i - 1].ls_corr);
1108 corr = lp->ls_corr;
1109 break;
1110 }
1111 }
1112 days = *timep / SECSPERDAY;
1113 rem = *timep % SECSPERDAY;
1114 #ifdef mc68k
1115 if (*timep == 0x80000000)
1116 {
1117 /*
1118 ** A 3B1 muffs the division on the most negative number.
1119 */
1120 days = -24855;
1121 rem = -11648;
1122 }
1123 #endif /* mc68k */
1124 rem += (offset - corr);
1125 while (rem < 0)
1126 {
1127 rem += SECSPERDAY;
1128 --days;
1129 }
1130 while (rem >= SECSPERDAY)
1131 {
1132 rem -= SECSPERDAY;
1133 ++days;
1134 }
1135 tmp->tm_hour = (int) (rem / SECSPERHOUR);
1136 rem = rem % SECSPERHOUR;
1137 tmp->tm_min = (int) (rem / SECSPERMIN);
1138 tmp->tm_sec = (int) (rem % SECSPERMIN);
1139 if (hit)
1140 /*
1141 ** A positive leap second requires a special
1142 ** representation. This uses "... ??:59:60".
1143 */
1144 ++(tmp->tm_sec);
1145 tmp->tm_wday = (int) ((EPOCH_WDAY + days) % DAYSPERWEEK);
1146 if (tmp->tm_wday < 0)
1147 tmp->tm_wday += DAYSPERWEEK;
1148 y = EPOCH_YEAR;
1149 if (days >= 0)
1150 for ( ; ; )
1151 {
1152 yleap = isleap(y);
1153 if (days < (long) year_lengths[yleap])
1154 break;
1155 ++y;
1156 days = days - (long) year_lengths[yleap];
1157 }
1158 else
1159 do {
1160 --y;
1161 yleap = isleap(y);
1162 days = days + (long) year_lengths[yleap];
1163 } while (days < 0);
1164 tmp->tm_year = y - TM_YEAR_BASE;
1165 tmp->tm_yday = (int) days;
1166 ip = mon_lengths[yleap];
1167 for (tmp->tm_mon = 0; days >= (long) ip[tmp->tm_mon]; ++(tmp->tm_mon))
1168 days = days - (long) ip[tmp->tm_mon];
1169 tmp->tm_mday = (int) (days + 1);
1170 tmp->tm_isdst = 0;
1171 tmp->tm_gmtoff = offset;
1172 }
1173
1174 /*
1175 ** A la X3J11
1176 */
1177
1178 char *
1179 asctime(const struct tm *timeptr)
1180 {
1181 static const char wday_name[DAYSPERWEEK][3] = {
1182 "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
1183 };
1184 static const char mon_name[MONSPERYEAR][3] = {
1185 "Jan", "Feb", "Mar", "Apr", "May", "Jun",
1186 "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
1187 };
1188 static char result[26];
1189
1190 (void) sprintf(result, "%.3s %.3s%3d %02d:%02d:%02d %d\n",
1191 wday_name[timeptr->tm_wday],
1192 mon_name[timeptr->tm_mon],
1193 timeptr->tm_mday, timeptr->tm_hour,
1194 timeptr->tm_min, timeptr->tm_sec,
1195 TM_YEAR_BASE + timeptr->tm_year);
1196 return result;
1197 }
1198
1199 char *
1200 ctime(const time_t * CPP_CONST timep)
1201 {
1202 return asctime(localtime(timep));
1203 }
1204
1205 /*
1206 ** Adapted from code provided by Robert Elz, who writes:
1207 ** The "best" way to do mktime I think is based on an idea of Bob
1208 ** Kridle's (so its said...) from a long time ago. (mtxinu!kridle now).
1209 ** It does a binary search of the time_t space. Since time_t's are
1210 ** just 32 bits, its a max of 32 iterations (even at 64 bits it
1211 ** would still be very reasonable).
1212 */
1213
1214 #ifndef WRONG
1215 #define WRONG (-1)
1216 #endif /* !defined WRONG */
1217
1218 static void
1219 normalize(int * CPP_CONST tensptr, int * CPP_CONST unitsptr, const int base)
1220 {
1221 if (*unitsptr >= base)
1222 {
1223 *tensptr += *unitsptr / base;
1224 *unitsptr %= base;
1225 }
1226 else if (*unitsptr < 0)
1227 {
1228 --*tensptr;
1229 *unitsptr += base;
1230 if (*unitsptr < 0)
1231 {
1232 *tensptr -= 1 + (-*unitsptr) / base;
1233 *unitsptr = base - (-*unitsptr) % base;
1234 }
1235 }
1236 }
1237
1238 static int
1239 tmcomp(const struct tm * CPP_CONST atmp, const struct tm * CPP_CONST btmp)
1240 {
1241 int result;
1242
1243 if ((result = (atmp->tm_year - btmp->tm_year)) == 0 &&
1244 (result = (atmp->tm_mon - btmp->tm_mon)) == 0 &&
1245 (result = (atmp->tm_mday - btmp->tm_mday)) == 0 &&
1246 (result = (atmp->tm_hour - btmp->tm_hour)) == 0 &&
1247 (result = (atmp->tm_min - btmp->tm_min)) == 0)
1248 result = atmp->tm_sec - btmp->tm_sec;
1249 return result;
1250 }
1251
1252 static time_t
1253 time2(struct tm *tmp, void (*const funcp)(const time_t * CPP_CONST, const long, struct tm *), const long offset, int * CPP_CONST okayp)
1254 {
1255 const struct state * sp;
1256 int dir;
1257 int bits;
1258 int i, j ;
1259 int saved_seconds;
1260 time_t newt;
1261 time_t t;
1262 struct tm yourtm, mytm;
1263
1264 *okayp = FALSE;
1265 yourtm = *tmp;
1266 if (yourtm.tm_sec >= SECSPERMIN + 2 || yourtm.tm_sec < 0)
1267 normalize(&yourtm.tm_min, &yourtm.tm_sec, SECSPERMIN);
1268 normalize(&yourtm.tm_hour, &yourtm.tm_min, MINSPERHOUR);
1269 normalize(&yourtm.tm_mday, &yourtm.tm_hour, HOURSPERDAY);
1270 normalize(&yourtm.tm_year, &yourtm.tm_mon, MONSPERYEAR);
1271 while (yourtm.tm_mday <= 0)
1272 {
1273 --yourtm.tm_year;
1274 yourtm.tm_mday +=
1275 year_lengths[isleap(yourtm.tm_year + TM_YEAR_BASE)];
1276 }
1277 for ( ; ; )
1278 {
1279 i = mon_lengths[isleap(yourtm.tm_year +
1280 TM_YEAR_BASE)][yourtm.tm_mon];
1281 if (yourtm.tm_mday <= i)
1282 break;
1283 yourtm.tm_mday -= i;
1284 if (++yourtm.tm_mon >= MONSPERYEAR)
1285 {
1286 yourtm.tm_mon = 0;
1287 ++yourtm.tm_year;
1288 }
1289 }
1290 saved_seconds = yourtm.tm_sec;
1291 yourtm.tm_sec = 0;
1292 /*
1293 ** Calculate the number of magnitude bits in a time_t
1294 ** (this works regardless of whether time_t is
1295 ** signed or unsigned, though lint complains if unsigned).
1296 */
1297 for (bits = 0, t = 1; t > 0; ++bits, t <<= 1)
1298 ;
1299 /*
1300 ** If time_t is signed, then 0 is the median value,
1301 ** if time_t is unsigned, then 1 << bits is median.
1302 */
1303 #ifdef _MSVCRT_LIB_
1304 t = (time_t) ((1 << bits) - 1);
1305 #else // TODO: FIXME: review which is correct
1306 t = (time_t) 1 << bits;
1307 #endif /*_MSVCRT_LIB_*/
1308
1309 for ( ; ; )
1310 {
1311 (*funcp)(&t, offset, &mytm);
1312 dir = tmcomp(&mytm, &yourtm);
1313 if (dir != 0)
1314 {
1315 if (bits-- < 0)
1316 return WRONG;
1317 if (bits < 0)
1318 --t;
1319 else if (dir > 0)
1320 t -= (time_t) 1 << bits;
1321 else t += (time_t) 1 << bits;
1322 continue;
1323 }
1324 if (yourtm.tm_isdst < 0 || mytm.tm_isdst == yourtm.tm_isdst)
1325 break;
1326 /*
1327 ** Right time, wrong type.
1328 ** Hunt for right time, right type.
1329 ** It's okay to guess wrong since the guess
1330 ** gets checked.
1331 */
1332 sp = (const struct state *)
1333 ((funcp == localsub) ? lclptr : gmtptr);
1334 #ifdef ALL_STATE
1335 if (sp == NULL)
1336 return WRONG;
1337 #endif /* defined ALL_STATE */
1338 for (i = 0; i < sp->typecnt; ++i)
1339 {
1340 if (sp->ttis[i].tt_isdst != yourtm.tm_isdst)
1341 continue;
1342 for (j = 0; j < sp->typecnt; ++j)
1343 {
1344 if (sp->ttis[j].tt_isdst == yourtm.tm_isdst)
1345 continue;
1346 newt = t + sp->ttis[j].tt_gmtoff -
1347 sp->ttis[i].tt_gmtoff;
1348 (*funcp)(&newt, offset, &mytm);
1349 if (tmcomp(&mytm, &yourtm) != 0)
1350 continue;
1351 if (mytm.tm_isdst != yourtm.tm_isdst)
1352 continue;
1353 /*
1354 ** We have a match.
1355 */
1356 t = newt;
1357 goto label;
1358 }
1359 }
1360 return WRONG;
1361 }
1362 label:
1363 t += saved_seconds;
1364 (*funcp)(&t, offset, tmp);
1365 *okayp = TRUE;
1366 return t;
1367 }
1368
1369 static time_t
1370 time1(struct tm * CPP_CONST tmp, void (*const funcp)(const time_t * CPP_CONST, const long, struct tm *), const long offset)
1371 {
1372 time_t t;
1373 const struct state * sp;
1374 int samei, otheri;
1375 int okay;
1376
1377 if (tmp->tm_isdst > 1)
1378 tmp->tm_isdst = 1;
1379 t = time2(tmp, funcp, offset, &okay);
1380 if (okay || tmp->tm_isdst < 0)
1381 return t;
1382 /*
1383 ** We're supposed to assume that somebody took a time of one type
1384 ** and did some math on it that yielded a "struct tm" that's bad.
1385 ** We try to divine the type they started from and adjust to the
1386 ** type they need.
1387 */
1388 sp = (const struct state *) ((funcp == localsub) ? lclptr : gmtptr);
1389 #ifdef ALL_STATE
1390 if (sp == NULL)
1391 return WRONG;
1392 #endif /* defined ALL_STATE */
1393 for (samei = 0; samei < sp->typecnt; ++samei)
1394 {
1395 if (sp->ttis[samei].tt_isdst != tmp->tm_isdst)
1396 continue;
1397 for (otheri = 0; otheri < sp->typecnt; ++otheri)
1398 {
1399 if (sp->ttis[otheri].tt_isdst == tmp->tm_isdst)
1400 continue;
1401 tmp->tm_sec += sp->ttis[otheri].tt_gmtoff -
1402 sp->ttis[samei].tt_gmtoff;
1403 tmp->tm_isdst = !tmp->tm_isdst;
1404 t = time2(tmp, funcp, offset, &okay);
1405 if (okay)
1406 return t;
1407 tmp->tm_sec -= sp->ttis[otheri].tt_gmtoff -
1408 sp->ttis[samei].tt_gmtoff;
1409 tmp->tm_isdst = !tmp->tm_isdst;
1410 }
1411 }
1412 return WRONG;
1413 }
1414
1415 time_t
1416 mktime(struct tm * tmp)
1417 {
1418 return time1(tmp, localsub, 0L);
1419 }